Add public scoreboard slug & URL

app/models/contest.rb

@@ -5,6 +5,7 @@
 #  id                 :integer          not null, primary key
 #  allow_registration :boolean          default(FALSE)
 #  name               :string
+#  slug               :string
 #  team               :boolean          default(FALSE)
 #  created_at         :datetime         not null
 #  updated_at         :datetime         not null
@@ -24,4 +25,7 @@ class Contest < ApplicationRecord
   has_many :completions, dependent: :destroy
   has_many :contestants, dependent: :destroy
   has_many :puzzles, dependent: :destroy
+
+  validates :name, presence: true
+  validates :slug, presence: true, format: { with: /\A(\w|-)*\z/, message: 'Only alphanumeric characters, "-" and "_" allowed.' }
 end